Plastic 'heals' itself when damaged

By Roger Highfield, Science Editor

12:00AM GMT 15 Feb 2001

A SMART plastic which "heals" itself when cracked or broken has been developed by scientists.

The material has been successfully tested by the University of Illinois. Like skin, the plastic begins to knit itself together as soon as it is cut, eventually regaining much of its original strength, the team reports today in Nature.

The substance, containing embedded microscopic capsules filled with a healing agent, provides a way to ensure the reliability of hard-to-repair components in spacecraft and space stations, satellites, rocket motors, artificial organs and bridge supports.

Plastics are made from chain-like chemicals called polymers, consisting of linked chains of chemical building blocks, and are susceptible to cracking caused by vibration, bending and heat. Often the damage is deep within a structure, where it is difficult to detect and almost impossible to repair.